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Date: Fri, 8 Sep 2017 15:10:35 +0200
From: David Sterba <dsterba@suse.cz>
To: linux-btrfs@vger.kernel.org
Subject: Re: test if a subvolume is a snapshot?
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On Fri, Sep 08, 2017 at 10:54:46AM +0200, Ulli Horlacher wrote:
> How can I test if a subvolume is a snapshot?

The inode number is 256 on a btrfs filesystem:

if [ stat -f --format=%T $path = btrfs -a stat --format=%i $path = 256 ]; ...

The directory that's result of snapshotting a subvolume, also called
EMPTY_SUBVOL has inode number 2, but that's not considered a normal
subvolume.